Question

1)21,8-(7*19/20-8*3/5) 2)-8,25-(-1/30+7/30) 3)3*1/14+2*3/7-(-2,85) 4)28-3 5/12+(-4,5+2 1/4) помогите решить пж срочно надо, заранее спасибо

Answer 1

Відповідь:

Покрокове пояснення:

21,8-(7*19/20-8*3/5)=436/20-(133/20-96/20)=436/20-37/20=399/20=

=19 19/20

-8,25-(-1/30+7/30)=-33/4-1=-165/20-4/20=-169/20=-8 9/20

3*1/14+2*3/7(-2,85)=3/14+6/7+2.85=30/140+120/140+399/140=549/140=

=3*129/140

28-3 5/12+(-4,5+2 1/4)=28-41/12-4,5+9/4=28-41/12-54/12+27/12=28-68/12=67/3

Answer 2

1) Calculation: 21.8 - (7 * 19/20 - 8 * 3/5)

To solve this calculation, we can follow the order of operations (PEMDAS/BODMAS), which stands for Parentheses/Brackets, Exponents/Orders, Multiplication/Division, and Addition/Subtraction.

Let's break down the calculation step by step:

1. Multiply 7 by 19/20: 7 * 19/20 = 133/20 2. Multiply 8 by 3/5: 8 * 3/5 = 24/5 3. Subtract the result of step 2 from the result of step 1: 133/20 - 24/5 = 133/20 - 96/20 = 37/20

Finally, subtract 37/20 from 21.8: 21.8 - 37/20 = (21.8 * 20 - 37) / 20 = (436 - 37) / 20 = 399/20 = 19.95.

Therefore, the result of the calculation 21.8 - (7 * 19/20 - 8 * 3/5) is 19.95.

2) Calculation: -8.25 - (-1/30 + 7/30)

Let's solve this calculation step by step:

1. Add -1/30 and 7/30: -1/30 + 7/30 = 6/30 = 1/5 2. Subtract the result of step 1 from -8.25: -8.25 - 1/5 = (-8.25 * 5 - 1) / 5 = (-41.25 - 1) / 5 = -42.25 / 5 = -8.45.

Therefore, the result of the calculation -8.25 - (-1/30 + 7/30) is -8.45.

3) Calculation: 3 * 1/14 + 2 * 3/7 - (-2.85)

Let's solve this calculation step by step:

1. Multiply 3 by 1/14: 3 * 1/14 = 3/14 2. Multiply 2 by 3/7: 2 * 3/7 = 6/7 3. Subtract -2.85 from the result of step 2: 6/7 - (-2.85) = 6/7 + 2.85 = (6/7 * 100 + 285) / 100 = (600/7 + 285) / 100 = (855/7) / 100 = 855/700 = 1.2214 (rounded to four decimal places).

Therefore, the result of the calculation 3 * 1/14 + 2 * 3/7 - (-2.85) is approximately 1.2214.

4) Calculation: 28 - 3 + 5/12 + (-4.5 + 2 + 1/4)

Let's solve this calculation step by step:

1. Add -4.5, 2, and 1/4: -4.5 + 2 + 1/4 = -4.5 + 2 + 0.25 = -2.25 + 2 + 0.25 = -0.25 2. Add 5/12 to the result of step 1: -0.25 + 5/12 = (-0.25 * 12 + 5) / 12 = (-3 + 5) / 12 = 2/12 = 1/6 3. Subtract 3 from the result of step 2: 1/6 - 3 = (1/6 * 6 - 18) / 6 = (1 - 18) / 6 = -17/6

Therefore, the result of the calculation 28 - 3 + 5/12 + (-4.5 + 2 + 1/4) is approximately -17/6.

I hope this helps! Let me know if you have any further questions.